Energy and Buildings – the environmental impact

Dr Andy Wright

Institute of Energy and Sustainable DevelopmentDe Montfort University

Overview• Challenges

– Energy– Climate change mitigation

• Demand reduction is part of the solution

• Priorities

• Examples

• Solutions

Key messages

• Resurgence in oil & gas production (fracking), especially USA, falling prices

• The world is still failing to make the global energy system more sustainable

• Energy efficiency is widely recognised as a key option in the hands of policy makers but is not reaching its full economic potential.

– tackling the barriers to energy efficiency…can unleash this potential and realise huge gains for energy security, economic growth and the environment. These gains are not based on achieving any major or unexpected technological breakthroughs, but just on taking actions to remove the barriers obstructing the implementation of energy efficiency measures that are economically viable.

• The climate goal of limiting warming to 2°C is becoming more difficult and more costly with each year

– Almost four-fifths of the CO2 emissions allowable by 2035 are already locked-in by existing power plants, factories, buildings, etc.

Global energy use

International Energy Agency – Key world statistics 2010

Kyo

to

Fos

sil f

uels

Breakdown

not much has changed in 35 years except that consumption has doubled!

International Energy Agency – Key world statistics 2010

World energy system 2010

Source: World energy outlook 2012

Past & future energy demand

Source: World energy outlook 2012

Projections – total primary energy supply under two IEA scenarios

International Energy Agency – Key world statistics 2010

~50% fossil fuel reduction from 1990

Climate Change

• Need to limit ‘expected’ temperature rise to 2°C, with a 4°C rise very unlikely

• The world needs to reduce greenhouse gas emissions by at least 50% by 2050

• UK has committed to an 80% reduction on 1990 levels (=77% reduction on 2008 levels)

• Buildings have a major part to play

Source: Committee on climate change

all for buildings

mostly for buildings

Carbon dioxide target - UK

Climate change, not global warming?

New York: Hurricane Sandy, October 2012

2013: Coldest spring for 50 years

July 2012: 100 flood alerts as UK braces for a month's rain in 24 hours

May 2012: Worcester

Energy efficiency must be a priority

• it reduces energy costs

• it reduces carbon dioxide

• it improves energy security

• it is usually much cheaper than ‘clean energy’

• (sometimes it costs nothing)

• …so why is it so difficult?

“The agenda is now dominated by energy and security. It is relatively easy to cut carbon by using lots of clean energy, but it is no longer acceptable as it dramatically pushes up cost” – Ant Wilson, AECOM

• We need to make our new buildings much more efficient in use as well as in design

• But we also need to make the existing stock much more efficient

• These issues are now (at last) firmly part of government policy

Energy efficiency deconstructed

need?

building fabric

control

system efficiency

clean energy supply

Examples – non-domestic buildingsfrom analysis of half-hourly gas, electricity and water data

We now have unprecedented access to high frequency energy and environmental data

Are we using it effectively?

Failure modes

• Heating (or cooling) out of season– Winter cooling or summer heating

• Heating when building unoccupied– Typically overnight, weekends

• Baseloads– Gas – lack of control– Water – usually a leak (not obvious in building)– Electricity – equipment, lights left on

• Excessive consumption (continuous)– Often gas with no time control and poor thermostatic control

• Most of these are much less likely in dwellings, because occupants would notice

Library: Heating control – gas on when clearly unoccupied

1 week:

red summer

black winter

Office: heating outside occupancy, high electricity baseload

1 week:

red summer

black winter

Office: water as occupancy proxy

no water: unoccupied

Weekend unoccupied heating

Total 282 sites (2004)

Sites with complete data 168

Unusualconfigurations 114

Flatlining or missing channel 83

Gas water electricityFeb 2004 all available 85

No unnecessaryweekend gas heating 59

Unoccupied weekendheating gas 26

Saturday AND Sunday unoccupied gas:fixed 24 hour pattern 4

continuously on 4

Saturday OR Sundayunoccupied gas 18

Sunday unoccupiedonly gas

fixed 24 hour pattern 8continuously on 9

Saturday unoccupiedonly gas

fixed 24 hour pattern 1Key

Not usedWorking correctly

End nodes - faulty control

31% problems

100% data available

21%9%

1.2%20%

69% OK

Energy use in industry

Over the past few years, a wide range of cheap, reliable, non-invasive monitoring equipment has become available

These include standalone loggers

clip-on electricity CTs

infra-red cameras

wireless systems

Why is energy efficiency difficult?

which is more complex – the aircraft or the buildings?

Conclusions: How to make buildings more efficient

• Make better use of data we already collect• Exploit new monitoring technology to

understand what’s going really on• Understand what the occupants are doing,

and why• Revaluate investment decisions – why

demand a 2 or 3 year payback?• Treat buildings more like aircraft (then they

might function as they’re designed)